Table 2.
Associations between 6-week change in mediator values and intervention group#.
| Main cohort* | Saliva cohort** | |||||||
|---|---|---|---|---|---|---|---|---|
| Change in mediator | SE | 95% CI | P value | Change in mediator | SE | 95% CI | P value | |
| Yoga versus self-care | ||||||||
| Fear avoidance | −0.24 | 1.39 | (−3.00, 2.52) | 0.865 | 2.67 | 1.87 | (−1.07, 6.41) | 0.158 |
| Self-efficacy | 0.78 | 0.30 | (0.19, 1.38) | 0.010 | 0.63 | 0.37 | (−0.10, 1.36) | 0.090 |
| Conscious awareness of body | 1.29 | 1.24 | (−1.16, 3.74) | 0.299 | −0.39 | 1.51 | (−3.41, 2.63) | 0.796 |
| Psychological distress | −1.17 | 1.56 | (−4.26, 1.92) | 0.456 | −1.42 | 1.89 | (−5.20, 2.36) | 0.455 |
| Perceived stress | −0.22 | 1.02 | (−2.24, 1.80) | 0.828 | −0.13 | 1.32 | (−2.77, 2.51) | 0.922 |
| Positive states of mind | 0.51 | 0.51 | (−0.50, 1.52) | 0.316 | 0.48 | 0.59 | (−0.70, 1.66) | 0.418 |
| Improved sleep | −0.20 | 0.10 | (−0.39, 0.00) | 0.050 | −0.20 | 0.13 | (−0.45, 0.06) | 0.131 |
| Hours of back exercise | 0.93 | 0.27 | (0.41, 1.46) | 0.0006 | 1.32 | 0.31 | (0.70, 1.95) | 0.00007 |
| DHEA change in diurnal average (log scale) | — | — | — | — | 0.19 | 0.13 | (−0.06, 0.44) | 0.139 |
| Average cortisol awakening response (CAR) | — | — | — | — | −0.12 | 0.27 | (−0.66, 0.42) | 0.658 |
| Stretching versus self-care | ||||||||
| Fear avoidance | −1.73 | 1.26 | (−4.23, 0.77) | 0.173 | −0.04 | 1.56 | (−3.16, 3.09) | 0.981 |
| Self-efficacy | 0.84 | 0.26 | (0.32, 1.36) | 0.002 | 0.75 | 0.36 | (0.03, 1.48) | 0.042 |
| Conscious awareness of body | 0.76 | 1.49 | (−2.18, 3.71) | 0.608 | −1.22 | 1.82 | (−4.85, 2.41) | 0.505 |
| Psychological distress | −2.06 | 1.62 | (−5.27, 1.16) | 0.207 | −0.17 | 2.07 | (−4.30, 3.96) | 0.934 |
| Perceived stress | −1.34 | 0.86 | (−3.05, 0.37) | 0.122 | −0.10 | 1.12 | (−2.35, 2.14) | 0.926 |
| Positive states of mind | 0.64 | 0.45 | (−0.25, 1.52) | 0.156 | 0.64 | 0.55 | (−0.45, 1.73) | 0.247 |
| Improved sleep | −0.07 | 0.10 | (−0.27, 0.12) | 0.448 | −0.04 | 0.13 | (−0.30, 0.22) | 0.765 |
| Hours of back exercise | 1.25 | 0.23 | (0.79, 1.71) | 0.000001 | 1.72 | 0.30 | (1.13, 2.32) | 0.0000002 |
| DHEA change in diurnal average (log scale) | — | — | — | — | 0.08 | 0.15 | (−0.21, 0.37) | 0.595 |
| Average cortisol awakening response (CAR) | — | — | — | — | 0.07 | 0.28 | (−0.50, 0.64) | 0.799 |
#Each mediator is an outcome variable in a model with intervention as the predictor variable and adjustment for selected baseline variables. Therefore, note that effect size comparison across rows should not be done since outcome variable is changing.
*Adjusted for baseline variables age, sex, BMI, back pain days, work type, pain travelling down the leg, bothersomeness, and RDQ. **Same adjustments as main cohort analysis with the addition of alcohol, tobacco, and medication use on the day of saliva sample collection.